WASHINGTON - Rep. John Lewis, who witnessed the signing of the Voting Rights Act into law in 1965 after he helped wage a bloody fight for civil rights in America, said today he was "shocked, dismayed and disappointed" the Supreme Court effectively struck down the heart of the landmark law.

"What the Supreme Court did was to put a dagger in the heart of the Voting Rights Act of 1965," Lewis told ABC News. "This act helped liberate not just a people but a nation."

Lewis, 73, who is among the last living leaders of the civil rights movement, called the decision "a very sad moment" for the nation. He stood in his congressional office, surrounded by black-and-white photographs from a bygone era and watched with ABC News as the Supreme Court released its ruling.

"I'm in disbelief that members of the Supreme Court would take this position," Lewis said. "We've come a distance. We've made progress, but there is still progress to be made."

A look of sadness fell across his face as the decision came down. With the Supreme Court essentially instructing Congress to update the voting rights provision, Lewis said he feared a polarized Congress would be unable to reach agreement.

"In 2006, we had the ability and capacity to come together in bipartisan fashion to renew the Voting Rights Act of 1965," Lewis said. "I'm not so sure whether we have the will to do what we must do and should do."

Lewis sat in the courtroom earlier this year during oral arguments on the voting rights case. He said he "really wanted to believe" the Supreme Court would uphold the entire Voting Rights Act.

"The Voting Rights Act has been very successful during the last 48 years," Lewis said, "but there are still problems all across the country where the Voting Rights Act needs to be strictly enforced."

Lewis, who in 1986 was elected to Congress from Atlanta, still has the scars from leading a march across the Edmund Pettus Bridge on March 7, 1965, in Selma, Ala., on a day that became known as Bloody Sunday. That protest, along with many others across the South, ultimately inspired President Johnson to sign the Voting Rights Act.

Lewis still has the pen that Johnson used to sign the landmark legislation, a law he said that would pave the way for the nation to elect its first black president four decades later.

"President Barack Obama wouldn't be the president of the United States if it hadn't been for the Voting Rights Act of 1965, so we have made progress," Lewis said, but he feared that a weakened Voting Rights Act would allow local election officials "to go back to another period.

"We don't want to go back. I'm shocked, dismayed, disappointed. I take it very personally," Lewis said. "I gave a little blood on that bridge for the right to vote, for the right to participate in a Democratic process."